Fig. 4 Early (<1000 GDD, solid bars), late (>1000 GDD, open bars), and total (solid and open bars combined) crude protein production in the spring of 1992 and 1993 for small grain cultivars seeded in monoculture. Bars containing or followed by the same letter are not significantly different (P < 0.05) according to Duncan's test. Root mean square errors for early, late, and total production, respectively, were 149, 100, and 186 for 1992 and 155, 71, and 189 for 1993